Asymmetric Michael addition of malonates to unsaturated ketones catalyzed by rare earth metal complexes bearing phenoxy functionalized chiral diphenylprolinolate ligands

作者：Qian, Qinqin; Zhu, Wenguo; Lu, Chengrong; Zhao, Bei^*; Yao, Yingming^*

来源：Tetrahedron: Asymmetry , 2016, 27(19): 911-917.

DOI：10.1016/j.tetasy.2016.07.014

• ORGANOCATALYTIC CONJUGATE ADDITION
• CARBON QUATERNARY STEREOCENTERS
• COMPATIBLE IMINIUM ACTIVATION
• LINKED-BINOL COMPLEX
• ALPHA,BETA-UNSATURATED KETONES
• IONIC LIQUIDS
• ENONES
• DERIVATIVES
• ALDEHYDES
• WATER

A simple, efficient catalytic asymmetric Michael addition of malonates to unsaturated ketones has been successfully developed. This process was promoted by rare earth metal complexes 1-4 bearing a chiral phenoxy functionalized prolinol ligand at room temperature [(LRE)-R-1((LH)-H-1) (H2L1 = (S)-2,4-di-tert-butyl-6-(2-(hydroxydiphenylmethyl)pyrrolidin-1-yl)methyl)phenol, RE = Yb 1, Y 2, Sc 3 and (LSc)-Sc-2((LH)-H-2) 4 (H2L2 = (S)-2,4-di-dimethylbenzy1-6-(2-(hydroxydiphenylmethyl)-pyrrolidin-1-yl)methyl)phenol)]. Complex 3 was the best catalyst in the transformation and the products were obtained in,up to 99% yield and with 90% ee. In addition, the molecular structures of the catalysts were well characterized, including X-ray determination of complex 3.

• 出版日期2016-10-15
• 单位苏州大学